FISHES. 103 



found in almost incredible numbers, and the concourses are known in England as ' eel- 

 fairs.' Ordinary obstacles may be overcome, and rapids of considerable slope may be 

 surmounted or evaded, but very high falls and precipitous banks arrest progress. As 

 already intimated, Niagara Falls is a barrier to their upward course, but, in the 

 words of Professor Baird, " in the spring and summer the visitor who enters under the 

 sheet of water at the foot of the falls will be astonished at the enormous numbers of 

 young eels crawling over the slippery rocks and squirming in the seething whirlpools. 

 An estimate of hundreds of wagon-loads, as seen in the course of the perilous journey 

 referred to, would hardly be considered excessive by those who have visited the spot 

 at a suitable season of the year." At other times large eels may be seen on their way 

 down stream, although naturally they are not as conspicuous then as are the hosts of 

 the young on their way up stream. Nevertheless, it is now a well-assured fact that 

 the eels are catadromous, that is, that the old descend the watercourses to the salt 

 water to spawn, and the young, at least of the female sex, ascend them to enjoy life 

 in the fresh water. 



The generation of the eel was long involved in great mystery, and the knowledge 

 thereof is one of the recent acquisitions of scientific investigation. So late, indeed, as 

 1880 it was declared by Dr. Giinther that "their mode of propagation is still un- 

 known." In want of positive knowledge, the rein has been given to loose hypothesis 

 and conjecture. It has been variously asserted that eels were generated from slime, 

 from dew, and from the skins of old eels or of snakes. The statement that they come 

 from horse-hairs is familiar to many country boys, and the origin of this belief is due 

 simply to the fact that there are certain aquatic worms, known under the generic 

 name Gordius, which are elongated and apparently smooth like the eel, and which 

 may be found in the same waters. It was one of the ideas of the Greeks to attribute 

 their paternity, as of many other doubtful offspring, to the convenient Jupiter. The 

 statement that they are viviparous has arisen from two causes, one the existence of 

 intestinal worms, and the other from the confusion of the eel with an elongated, and 

 consequently eel-like, but otherwise very different form, the Zoarces viviparus. The 

 Zoarces is, indeed, in Germany as well as in the Scandinavian countries, generally 

 known as the Aal-rautter, or eel-mother, and thus in its name perpetuates the fancy. 

 Even where eels are to be found in extreme abundance, and where they are the objects 

 of a special culture, like erroneous opinions prevail. Thus, according to Jacoby, about 

 the lagoon of Comacchio, there is an " ineradicable belief among the fishermen that the 

 eel is born of other fishes ; they point to special differences in color, and especially in 

 the common mullet, Mugil cephalus, as the causes of variation in color and form 

 among eels. It is a very ancient belief, widely prevalent to the present day, that eels 

 pair with water-snakes. In Sardinia the fishermen cling to the belief that a certain 

 beetle, the so-called water-beetle, Dytiscus roeselii, is the progenitor of eels, and they 

 therefore call this 'mother of eels.' " The assignment of such maternity to the water- 

 beetle is doubtless due to the detection of the hair-worm, or Gordms, in the insect by 

 sharp sighted but unscientific observers, and, inasmuch as the beetle inhabits the same 

 waters as the eel, a very illogical deduction has led to connect the two together. 



All such beliefs as have been thus recounted are due to the inconspicuous nature 

 of the generative organs in eels found in fresh waters and at most seasons — a charac- 

 teristic which is in strong contrast to the development of corresponding parts in fishes 

 generally. Nevertheless, the ovaries of the eel were discovered, as long ago as 1707, by 

 Dr. Sancassini, of Comacchio, and described by the celebrated Valisneri (after whom the 



